I became a member of this exclusive Club and the interest in membership in the Club was there. But it was... there were not many people who would be willing to go through the details and spend the time studying the system to learn it. So we were more or less alone. But then almost overnight I would... that's an exaggeration, but it's not too strong exaggeration. The situation has changed dramatically. Suddenly it seemed like the whole world was interested in H2. For me the breakpoint, the overnight, came at one meeting, which was in Asilomar in California in the West Coast. A very nice place. Big Sur is very close to it, and one of the loveliest part of California. But there I gave a talk and I expected the same thing would happen basically as before, but suddenly I mean the discussion wouldn't stop. It was... they were just... I mean you could see it on their faces. They were waiting for every word and then there were questions, interruptions, and didn't end the discussion for long into the break. So it was really very dramatic.

Born in 1936, Jan Klein is a Czech-American immunologist who co-founded the modern science of immunogenetics – key to understanding illness and disease. He is the author or co-author of over 560 scientific publications and of seven books including 'Where Do We Come From?' which examines the molecular evolution of humans. He graduated from the Charles University at Prague in 1955, and received his MS in Botany from the same school in 1958. From 1977 to his retirement in 2004, he was the Director of the Max Planck Institute for Biology at Tübingen, Germany.

Colm O'hUigin is a senior staff scientist at the US National Cancer Institute. He received his BA, MSc and PhD at the Genetics Department of Trinity College, Dublin where he later returned as a lecturer. He has held appointments at the Center for Population and Demographic Genetics, UT Houston, and at the University of Cambridge. As an EMBO fellow, he moved in 1990 to the Max Planck Institute for Biology in Tübingen, Germany to work with Jan Klein and lead a research group studying the evolutionary origins of immune molecules, of teeth, trypanosomes and of species.